Seasonal affective disorder, also known as winter depression, winter blues, summer depression, summer blues, or seasonal depression, was considered as a mood disorder in which people who have normal mental health throughout most of the year experience depressive symptoms in the winter.
Winter depression is a common slump in the mood of some inhabitants of most of the Nordic countries.
In the Diagnostic and Statistical Manual of Mental Disorders, winter depression is no longer classified as a unique mood disorder, but is now a specifier called with seasonal pattern for recurrent major depressive disorder that occurs at a specific time of the year and fully remits otherwise. Although experts were initially skeptical, this condition is now recognized as a common disorder. SAD's prevalence in the U.S. ranges from 1.4% in Florida to 9.9% in Alaska.
The U.S. National Library of Medicine notes that some people experience a serious mood change when the seasons change. They may sleep too much, have little energy, and may also feel depressed. Though symptoms can be severe, they usually clear up.
There are many different treatments for classic (winter-based) seasonal affective disorder.
Treatments for classic (winter-based) seasonal affective disorder include light therapy, medication, ionized-air administration, cognitive-behavioral therapy and carefully timed supplementation of the hormone melatonin.
Photoperiod-related alterations of the duration of melatonin secretion may affect the seasonal mood cycles of SAD. This suggests that light therapy may be an effective treatment for SAD. Light therapy uses a lightbox emitting far more lumens than a customary incandescent lamp. Bright white “full spectrum” light at 10,000 lux, blue light at a wavelength of 480 nm at 2,500 lux or green light at a wavelength of 500 nm at 350 lux are used, with the first-mentioned historically preferred.
Bright light therapy is effective with the patient sitting a prescribed distance, commonly 30-60 cm, in front of the box with her/his eyes open, but not staring at the light source for 30-60 minutes. But many of patients find lightbox treatment inconvenient and as many stop use because of this.
Dawn simulation has also proven to be effective in some studies.
Light therapy can also consist of exposure to sunlight, either by spending more time outside or using a computer-controlled heliostat to reflect sunlight into the windows of a home or office. Although light therapy is the leading treatment for seasonal affective disorder, prolonged direct sunlight or artificial lights that don't block the ultraviolet range should be avoided due to the threat of skin cancer.
SSRI (selective serotonin reuptake inhibitor) antidepressants have proven effective in treating SAD, also. Bupropion is also effective as a prophylactic. Effective antidepressants are fluoxetine, sertraline, or paroxetine.
An explanation for winter depression is that vitamin D levels are too low when people do not get enough Ultraviolet-B on their skin. Thus, an alternative to using bright lights is to take vitamin D supplements.
Another disorder of a reduced light exposure is the change of the human skin during the winter period, whereupon the skin dries out and remoisturization of the skin is disturbed due to the reduced light exposure. That results in the consequence often, that humans develop neurodermatitis in the winter.
The problems of the therapies known in the state of the art are beside the undesirable effects during and after the administration of hormones, antidepressants and vitamin D to the humans that many of patients find lightbox treatment inconvenient and as many stop use because of this. Moreover the exposure to sunlight or artificial light needs time and requires the patient removes most of their clothes.
It could therefore be helpful to find a human exposure to light in all situations when light from a light source is available, particularly, to find a possibility that human skin can be exposed to light even though the human is covered with clothes.